1. Field of the invention
This invention relates to heat exchanger assemblies. More specifically, this invention relates to air cooled heat exchanger assemblies having a plurality of fans for directing air flow.
2. Description of the prior art
The use of heat exchanger assemblies including a plurality of fans is well known in the art. For example, U.S. Pat. No. 3,627,037 issued to Carr on Dec. 14, 1971 discloses such an arrangement.
The Carr Patent discloses a factory assembled heat exchanger apparatus to permit an increase in the capacity of the heat exchanger without exceeding permissible height and width limits for transportation of the assembled unit on highways and railroads. The apparatus includes a plurality of fans having fan shafts which are in axial alignment and may be coupled for rotation of the fans in unison. The fans are mounted in parallel planes and draw air in from right and left sides of the heat exchanger apparatus. The air which is drawn by each fan is pushed upward by virtue of a separate venting wall associated with each fan such that the air passes through a heat exchanger unit mounted on the top of the length-to-length arrangement of the fans and associated venting walls.
The prior art further includes the following U.S. patents:
______________________________________ U.S. Pat. No. Inventor(s) Date Issued ______________________________________ 3,384,165 Mathews May 21, 1968 3,403,725 Miner Oct. 1, 1968 3,628,590 Knebusch Dec. 21, 1971 3,727,679 Von Cleve Apr. 17, 1973 ______________________________________
The Mathews Patent discloses a heat exchanger unit including several different fans causing air flow across various heat exchanger sections which are inclined within the body of the unit. Air flow is induced across some of the heat exchangers by a fan, whereas air is also forced across heat exchangers by another fan. The fans blow straight up or straight down.
The Miner Patent discloses a fan arrangement including a number of axially aligned fans with deflectors or venting walls associated to push air upwardly. Alternate embodiments show a heat exchanger having air forced through it by the fans and a heat exchanger having air induced to flow through it by the fans.
The Knebusch Patent discloses a heat exchanger unit having two separate coil sections slanted within the body of the unit. Alternate embodiments use a blower for inducing air flow across a cooler and for forcing air through a cooler.
The Von Cleve Patent discloses a heat exchanger including alternate constructions whereby fans may be used for either induced or forced air circulation. The heat exchanger sections are inclined relative to the fans.
Although the prior art has provided generally useful heat exchanger assemblies, they have generally been subject to a number of disadvantages. For example, a heat exchanger assembly may require excessive volume if it is desired to increase its capacity beyond certain limits. Limitations in the cooling capacity per unit volume of the assembly have generally resulted in excessively large structures when large quantities of heat must be dissipated.
The above discussed Carr Patent discloses a heat exchanger assembly having a relatively high heat dissipation capacity, but still remaining sufficiently small to allow it to be transported by highway and railroad. Although this has lessened the capacity and volume problems discussed above, the capacity of this heat exchanger assembly is still somewhat limited due to the size considerations.